Nimbus

A series of seven NASA weather satellites,
launched between August 1964 and October 1978 into polar orbits, which photographed
cloud cover and monitored air pollution. It followed the first generation
of US meteorological satellites known as TIROS.
Nimbus helped develop the technology that would be used in later meteorological
programs.

The name "Nimbus" is the meteorological term for precipitating clouds (from
the Latin for "rainstorm" or "cloud"). It was suggested in late 1959 by
Edgar Cortright, Chief of NASA's Advanced
Technology Programs, who directed the formation of NASA's meteorological
satellite programs, including Nimbus and TIROS.